Oil-well drill bit



R. 1. BROWN. OIL WELL DRILL BIT. I APPLICATION FILED JULY 26,1921-i,421,396, Patented July 4, 1922.

2 SHEETSSHEET 1.

R. J BROWN.

OIL WELL DRILL BIT,

APPLICATION FILED JULY 26,1921.

1 ,42 1 396 Patented July 4, 1922.

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@NETEEE STATES aren't eer e ROBERT J. BBOVVN, OE MERBYVILLE, LOUISIANA,ASSIGNOR OF ONE-HALF T0 J. F. WALDEN, OF MEB-RYVILLE, LOUISIANA.

OIL- ELL DRILL BIT.

Application filed July 26,

T 0 all wit-0m 2'2? may concern.

Be it known that 1, ROBERT J. BROWN, a citizen of the United States,residing at Merryville, in the parish of Beauregard, State of Louisiana,have invented a new and useful Oilell Drill Bit; and I do hereby declarethe following to be a full, clear, and exact description of theinvention, such as will enable others skilled in the art to which itappertains to make and use the same.

The invention relates to oil well drill bits and has for its object toprovide a device of this character so constructed that the bit may beeasily and quickly positioned in advance of the casing and ininterengagement with said casing so as to rotate therewith and alsoeasily and quickly removed from a position in advance of the case andremoved from the casing without removing the casing.

A further object is to provide an oil well drill bit comprising a drillbit shank adapted to be disposed in a casing, said drill bit shankhaving pivotally mounted in the lower end thereof, crossed blades, thelower ends of which are adapted to be received in notches in the lowerend of the well casing when the shank is lowered into the casing therebyinterengaging the casing and revolving with said casing. Also to providea locking pin adapted to be disposed between the upper end of thecrossed bit blades for locking said blades in extended position.

A further object is to provide vertically movable trip bars slidablymounted in the drill bit shank and cooperating with the upper ends ofthe bit blades for forcing said blades inwardly after the locking pinhas been removed, thereby moving the lower ends of the bit blades out ofengagement with the casing and allowing the removal of the drill bit asa whole.

With the above and other objects in view the invention resides in thecombination and arrangement of parts as hereinafter set forth, shown inthe drawings, described and claimed, it being understood that changes inthe precise embodiment of the invention may be made within the scope ofwhat is claimed without departing from the spirit of the invention.

In the drawings Figure 1 is a side elevation of the lower Specificationof Letters Patent.

1921. Serial No. 487,648.

end of an oil well casing, showing the drill bit therein.

Figure 2 is a horizontal sectional view taken on line 2-2 of Figure 1.

Figure 3 is a vertical sectional view through the drill bit shank andthe lower end of the'casing.

Figure 4 is an enlarged detail view of a portion of one of the bitblades and one of the trip bars, shown in section.

Figure 5 is a perspective view of the drill bit shank.

Referring to the drawings, the numeral 1 designates the lower end of aconventional form of well casing and 2 a reinforcing therein, whichreinforcing braces the lower end of the casing 1 as it is revolved, andalso reinforces the casing at the point where it interengages with thebit blades 3, which bit blades are received in the notches 5 in thelower end of the well casing and are preferably diametrically disposed.When the well casing 1 is rotated it will be seen that the bit blades 3will rotate therewith and drill or bore in advance of the casing in sucha manner that the casing will follow the boring operation.

It has been found that at times it was necessary to remove the drillbits 3 from the casing, therefore to accomplish this object the bits 3are disposed in a vertical slot 6 in the reduced portion 7 of a drillshank 8, said blades being crossed and pivoted on a transverselydisposed pin 9. The arms 10 of the blades 3 extend upwardly and arespaced from each other in such a manner when the locking-pin 11 isforced between the arms the outwardly extending portions 12 of the bladewill move outwardly and upwardly and into engagement with the notches 5.The locking pin 11 extends through the drill bit shank 8 and is carriedby a follower block 13, which follower block when raised also raises thepin 11, thereby allowing the arms 10 of the bits 3 to move toward eachother and consequently moving the arms 12 of the blades inwardly.Extending vertically through the follower block 13, and the drill bitshank 8 are trip bars 14, which trip bars are provided with abutments15, which when the bars are moved vertically engage the inclinedsurfaces 16 of the arms 10 of the blade and force said arms inwardly,after the locking pin 11 has been removed by Patented July 4,1922.

with abutments 17, which abutments engage the abutments 18 in the bitshank 8 and limit the upward movement of the trip bars, and

at the same time form means whereby upon a continued upward pull on thesuspending cable 19, the bit shank and bits will be removed from thecasing without removing the casing from the hole that is being drilled.

To withdraw the bit from the casing 1, the casing is first lifted a fewfeet which allows the bevelled edge 20 of the casing 1 to move intoengagement with the bevelled portion 21. of the bit shank 8. After theparts have been so moved it will be seen that the bit blades 3 will bedisposed below the lower end of the casing 1 and out of engagement withthe recesses 5 therein. Then by means of the cable 22 connected to thefollower block 13, said follower block is raised, thereby moving thelocking pin 11 from between the arms 10 of the bit blades 3. After thelocking pin 11 has been removed the trip bars 14 are raised, whichaction. will force the arms 10 of the bit blades inwardly therebypositioning the arms 12 thereof upon a continued upward movement of thefollower block and upward movement of the bit shank, said bit shank,follower block and bit blades may be removed from the casing,

To reinsert the drill bit in the casing, the device is placed in thecasing at the upper end and lowered therein. until the bevelled portion21 engages the bevel portion 20. Then the follower block which is ofsufficient weight will force the lock pin 11 between the arms 10 ofthebit blades 3 and securely lock said bit blades in extended position.After the bit blades have been extended and locked,

the casing 1 is lowered until the bit bladesrest on the ground and thecasing under its weight moves downwardly on the bit shank until it restson the upper edges of the arms 12 of the bit blades 3. The lower edge ofthe casing 1 being in engagement with the arms 12 of the bit blades, itwill be seen that upon rotation of the casing 1 the upper edges of thearms 12 of the bit blades will be received in the notches 5 of thecasing and consequently as the casing continues to, rotate for drillingoperation the bit blades will be rotated therewith in such a manner thatthe casing will advance with the drilling operation.

From the above it will be seen that a drilling device for drilling oilwells is provided,

which device is particularly adapted for deep drilling where thedrilling is acc0mquickly placed in position in advance of the casing orremoved from a position in advance thereof whenever desired.

The invention having been set forth what is claimed as new and usefulis 1. A well drilling device comprising a casing having diametricallydisposed notches in the lower end thereof, a drill bit shank verticallymovable in said casing and having its lower end provided with abifurcation, crossed pivoted bit blades disposed in said bifurcation,said bit blades being provided with outwardly extending arms andupwardly extending arms, a vertically movable locking pin carried by thebit shank and forming means for locking the upwardly extending armsagainst inward movement and the outwardly extending arms againstdownward movement, and trip bars vertically movable in the shank andhaving their lower ends positioned to cooperate with the upwardlyextending arms of the bit blades for forcing said bit blades inwardlyafter the locking pin has been removed. I

2. A well drilling device comprising a casing having diametricallydisposed notches having outwardly extending and upwardly extending arms,a verticaly movable locking pin. extending through the bit shank, afollower block carrying said locking pin, the upwardly extending armsbeing so shaped that the locking pin may be forced therebetween forextending the outwardly extending arms to a position where they will bereceived by the notches in the lower end of the casing, verticallymovable trip bars extending through the bit shank and the follower blockand cooperating with the upwardly extending arms for forcing'the sametogether after the locking pin has been removed, and means whereby thefollower block and the bit shank may be raised.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

ROBERT J. BROWN.

Witnesses J; B. WALTERS, H. C. MORGAN.

